Fluid pressure responsive regulating means for use in liquid supply systems



Dec. 18, 1951 R. J. IFIELD 2,579,147

FLUID PRESSURE RESPONSIVE REGULATING MEANS FOR USE IN LIQUID SUPPLY SYSTEMS Filed April 14, 1948 2 SHEETS-SHEET].

1951 R. J. [FIELD FLUID PRESSURE RESPONSIVE REGULATING MEANS FOR USE IN LIQUID SUPPLY SYSTEMS Filed April 14, 1948 2 SHEETS-SHEET 2 Fig.3

L71) 6 121 451 JIfL'eLCL Patented Dec. 18, 1951 XSIEEMS.

ichard oseph meld. r,,.

Australia, as's ig'noito J osie Birminghammngland South Wales was AppIicatiOnApriL 14, 1945,- s r al No. 20,913; i-q ffl i t none were Y when; uid. ue1. s up ied o h g qmbu t on the b .Qiai pr mlls on rb e rime? move through aburner? nozzle adapted toiinpart swirlinef'mo ionto e i idi t a JQWI Pr ee oisi p l h iqui i q h v no e xc s. of theamountr e uir dc oibedischa e a o e: ur he zs essito he vstmo r iricii a n be n je uir dtqe b e t m mswifl i jr itions' ojhe in amed n t zle-t 1 2 t] a; kn wn; racti to r v e fithl s s m means fQI WI QPA ZiQ 1 X c nt ol in th at vo flowo thefre nrhe xc ss. h sa d means. eing es n iv o, acts... eia ed w hi hle workingconditions of the prime mov r.

The qbieeto the, r s nt i e t on. is o r i nnimpretd i r tu n-flow; senat r ad pted o. e. s sive t the m 16 he p i o the ombust on h iib, vablqwr h ch are:

sflldr venlbylthe ie QYer- "The nveni pn' c mp ises thecomb a on of elicit adar it v t re connec ed the eiurjeleflerr, pa t ith s stem a a vef r eqn re linejthe inlet to the duct en an ther va v a: son trolling a bypass from the, duct, the inlet valve havingcombined with it actuating means responsive to the diiierenc e between the blowerair pressure and the returned-fuel pressure, andthe by-pass valve being responsive to the blowerair pressure.

In the accompanying drawings:

s-cl imsr (c1. 157%1532:

Figure 1 is a side elevation, in section, of a return-flow regulator for the purpose described, constructed in accordance with the invention;

Figure 2 is an end elevation, partly in section, of the regulator shown in Figure 1;

Figure 3-is a diagram showing the manner in which the regulator is connected in a returnfiow system for supplying fuel to the burner nozzle of a combustion chamber.

In carrying the invention into effect according to one convenient mode as illustrated in Figures 1 and 2, a hollow body part I is provided which is divided into two compartments 2 and 3 by a flexible diaphragm 4. A cover 5 for the compartment 2 has a sleeve portion 6 extending with.- in the compartment and engaging a ring '1 which holds the diaphragm upon a shoulderB. A member 9 secured to the central portion of the diaphragm is connected to an elastic capsule ID the interior of which is evacuated, the capsule being .adjustably supported by a bolt ll rotatable in a cover l2 screwed to a centrally bored boss l3 on the main cover 5. The bore in the boss l3 receives a slidable spindle 1 attached to the cap- L1l l0 and threaded to receive the bolt H.

V, uite e xby the lower, lim or a carr ed i member ll t e he ethe a 4. A rforated spring disQ 'ZB attache tether 7 memb r, L sho ld ithjthegruer subm t, ta ks, or; o he 198 nlet endbifth.

seating 23 with whichco ope annede di m? i T si sigure emerge W. described isshownat'flahd I e iiel 'pumpat 33. The outlet of the fuel pump is connected to the nozzle 34, the return flow from which is led to the connection 30 of the regulator. The outlet 22 from the chamber 3 of the regulator is connected to the inlet of the pump 33 as also is the fuel supply tank 35. The endof theduct l5 ope posite to the valve 24 is connected through an 1 adjustable. choke 36, which may be of any? con-f venient construction,'to theinlet of the iu'el pump 33. The connection 291 communicating with the compartment 21 of the regulator 32 is connected to the partof the system which conveys the blower air.

The mode of action of the regulatorahoveedea scribed is as follows: 1 v

Normally the by-pass valve I1 is closed, andthe inlet valve 24 is open. During ordinary working. conditions in the combustion chamber the inlet valve 24 is held open by the excess of the pressure of the liquid returned from the burner over? the blower-air pressure. The returned: liquid 3 and in particular the path leading from the connection 22 directly to the inlet side of the pump 33, when the speed of the prime mover exceeds a predetermined rate. ,In.the event of this speed beingflexce'eded the correspondingly increased pressure of the blower-air causes the by-pass valve to open. Normally this valve is for controlling the admission of liquid fuel under pressure to one end of the duct, a second valve controlling the by-pass, means responsive to the difference between the fuel pressure and a variable air pressure for actuating the-first valve, and means responsive to the last mentioned pressure for actuating the second valve when that held closed by the preponderance of fluid pressure acting on the underside of the diaphragm 14. From inspection of Figure l it'will be seen that blower-air pressure in the chamber 2 and acting on the opposite end of thecapsule 10 tends to contract the capsule. Thistendency is opposed by the pressure of the blower-air on the dia-' phragm 4 which is of suficiently larger diameter .to give the desired result. The upper-side of the diaphragm i therefore subject to' a force corresponding to the difference of the areas or the diaphragm and capsule, and tending to open the valve. But at all normal working speeds this force is less than that exerted on the underside of the diaphragm, and the valve remains closed. When the blower-air pressure exceeds a certain amount corresponding to the excess speed of the prime mover, the effective pressure acting on the upper side of the diaphragm exceeds the pressure acting on the underside, and causes the by-pass valveto open.

In the event of the pilot reducing the supply of fuel to the burner nozzle, causing a corresponding drop of fuel pressure acting on the diaphragm 25, the then preponderating blowerair pressure acting on the other side closes the valve 24, and so interrupts the return flow from the nozzle, and thereby prevents risk of extinction of the flame in the combustion chamber due to inadequacy of 'fuel supply.

By this invention the required control of the return flow by the blower-air pressure can be efiected in a simple and reliable manner.

Having thu described my invention what I claim as new and desire to secure by Letters Patent is:

1. Flow-controlling means for liquid fuel under pressure, comprising in combination a duct having a by-pass intermediate its ends, a first valve pressure exceeds a predetermined amount.

2. Flow-controlling means for liquid fuel under pressure, comprising in combination a hollow body, a flexible diaphragm dividing the hollow body. into primary and secondary pressure compartments, an inlet through which air under variable pressure can be admitted to the primary pressure compartment, the secondary pressure compartment having an opening for maintaining a relatively low pressure in the interior of the secondary pressure compartment, a duct extending across the secondary pressure compartment and having a by-pass within the secondary pressure compartment, an inlet for liquid fuel under pressure, a first valve controlling communication between the fuel inlet and one end of the duct, a second valve controlling the by-pass, means for actuating the first valve in response to the difference between the pressures of.the air and liquid fuel supplied to the inlets, an evacuated capsule of smaller effective area than the diaphragm arranged in the primary pressure compartment and connected to the diaphragm, and means connecting the second valve to the diaphragm so that the second valve is opened when the air pressure in the primary compartment exceeds a predetermined amount.

3. Flow-controlling means as claimed in claim 2 and comprising the combination with the hollow body, of a chamber divided into two compartments by a second diaphragm which carries and forms the mean for actuating the first valve, one of the two chamber compartments being in communication with the fuel inlet, and the other being in communication with the air inlet and the primary pressure compartment.

RICHARD JOSEPH IFIELD.

No references cited. 

